Nearly a quarter of Covid-19 cases in Gibraltar are asymptomatic

By Gabriella Peralta and Brian Reyes

Nearly one in four Covid-19 infections detected in Gibraltar have been asymptomatic, the Gibraltar Government said, as it intensified testing and contact tracing to swiftly detect and isolate cases.

The percentage of asymptomatic cases detected is a reflection of a rigorous rolling programme that has seen 23,623 tests carried out since the pandemic began.

Although initially testing was limited solely to individuals with Covid-19 symptoms, over the past months this has been ramped up to include a wider cross-section of the community.

Random tests on the public, targeted frontline sampling, testing on request and, more recently, testing stands outside local supermarkets and on Main Street have helped Public Health to obtain a clearer snapshot of the spread of the virus in the community.

Yesterday the Government reported some nine active cases of Covid-19, of which seven were residents and two visitors.

There are also 163 people currently in self-isolation.

The consistent testing has provided a searchlight to assess the spread, and of the 193 cases detected in Gibraltar to date since the start of the pandemic, 45 have been asymptomatic, with remaining cases having displayed symptoms.

A random sampling of the public conducted earlier this year, during which 400 people were tested returned, returned just 10 positive results, although the situation has evolved since.

Workers from 62 categories of jobs from the public and private sectors have been tested routinely, ranging from healthcare and law enforcement officers to workers in the retail and construction sectors.

A total of 9,832 tests have been carried out so far among the frontline, targeted and systematic sampling.

From the targeted screening of frontline workers, 35 have tested positive for Covid-19.

Contact tracing, which has been considered key to the preventing a spread, has seen 316 people asked to self-isolate.

Of these 316 people, five close contacts have tested positive, a Government spokesman confirmed.

“Many more had symptoms but were either not tested, as they were in isolation, or were not positive at the time they were tested,” the spokesman said.

CONTACT TRACING APP

Work to improve contract tracing has been aided by the BEAT Covid app and the Government has strongly urged the public to download it after its release last June.

Following privacy concerns worldwide over contact tracing apps, the Gibraltar Government has stressed that the app, which uses a system developed by Apple and Google, is “completely anonymous” and no personal data is logged or shared with anyone at any time.

The app works via Bluetooth and runs in the background after being downloaded. It only registers other nearby phones that have the app and no personal data is logged or shared with anyone.

If a user has been in contact with someone who tests positive, the phone will receive an alert in a completely anonymous manner.

Many European countries have achieved some early successes with their contract tracing apps, with millions of people having downloaded the smartphone apps and hundreds have uploaded the results of positive Covid-19 tests.

In Gibraltar, the BEAT COVID App has been downloaded 15,000 times from the Apple and Google Play Stores. The downloads are almost equally divided between Android and iOS devices, according to the Gibraltar Government.

Yet most European countries, Gibraltar among them, so far lack solid evidence that their apps - which identify close contacts via Bluetooth connections with nearby users - are actually alerting people who may have caught the disease before they can infect others.

"I find it quite strange that many of the systems are designed not to be able to monitor and evaluate," said Michael Veale, a lecturer at University College London.

The Apple-Google framework does in fact allow for some data collection, at the same time making it impossible for governments to stalk their own citizens.

Ireland, which uses the same standard, is showing the benefits of being a bit less privacy-obsessed.

Its Covid Tracker app, which has been downloaded by 30% of the population, tallies how many people upload a positive test result and how many get notifications.

"We're seeing the whole end-to-end flow and success from that perspective," said Colme Harte, technical director at NearForm, the software development firm that created the Irish app.

A total of 58 users registered positive tests in the app's first three weeks of operation through to July 28, generating 137 close contact alerts. Of these, 129 opted to get a follow-up call from Ireland's contact tracing team.

While the numbers are small, partly reflecting Ireland's low levels of infection with the flu-like illness, publishing them helps to show that people can make a contribution to fighting the pandemic by downloading the app.

"It helps build trust that it is worth actually installing the app," Mr Harte told Reuters.

The Irish app has inspired spinoffs, including Gibraltar’s own app.

But while Ireland harvests some anonymised data, Gibraltar does not, leaving public health officials largely blind as to how effective the app is.

There has been just one occasion where the GHA has logged a positive case involving a person who had downloaded the app and alerted officials to that fact.

“[But] no personal data is logged or shared with anyone at any time, so the Government is not able to monitor the number of alerts [issued through the app],” a Government spokesman told the Chronicle.

“We do not know the number of alerts that may have been issued as a result of this case.”

The GHA and the Contract Tracing Bureau monitors and cares for patients who have tested positive for Covid-19.

Contact tracing is an important part of the public health response to the Covid-19 virus.

Anyone who is infected is asked to identify persons they have interacted with in the days leading up to their being diagnosed with the virus.

Health practitioners then contact those at risk of infection to warn them of potential exposure.

The BEAT Covid Gibraltar App aims to automate the process of contact tracing and support the work of the Contact Tracing Bureau.

“Those who receive the app notification will be directed to a website which will allow them to get in contact with the Contact Tracing Bureau who will provide them with appropriate advice,” the spokesman added.

“The goal is to, as quickly as possible, reduce the further transmission of the Covid-19 virus by informing app users that they have been close to a person who has tested positive.”

The Government added that the more people that download the app, the more effective it will be.

Work is also under way to ensure that Gibraltar’s app can work with similar apps in other countries, particularly the UK and Spain.

“Interoperability is an important part of the development work being done,” the spokesman said.

Spain is currently testing its contact tracing app – based on the Apple/Google framework - and is planning to roll out the app in September.

Separately, the Gibraltar Government is in close communication with the UK's NHSX team which is developing the UK’s contact tracing app, and with the Irish and Northern Ireland Governments in the development of their apps.

NHSX are negotiating with the EU’s eHealth Network to ensure a safe exchange of information between national contact tracing apps based on Apple/Google’s decentralised architecture.

People with GHA cards wishing to have a Covid-19 test and do not have any symptoms can ring the 200 41818 to request a test. Those with symptoms should continue to ring the 111 number and self-isolate as soon as symptoms occur.